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Phytoplankton Calcification in a CO2-Accreting Ocean
Reference
Iglesias-Rodriguez, M.D., Halloran, P.R., Rickaby, R.E.M., Hall, I.R., Colmenero-Hidalgo, E., Gittins, J.R., Green, D.R.H., Tyrrell, T., Gibbs, S.J., von Dassow, P., Rehm, E., Armbrust, E.V. and Boessenkool, K.P. 2008. Phytoplankton calcification in a high-CO2 world. Science 320: 336-340.

Background
For the past several years, the ongoing rise in the air's CO2 content has been claimed by the world's climate alarmists to be making life ever more difficult for earth's calcifying marine organisms by lowering the calcium carbonate saturation state of seawater, which phenomenon has been predicted by them to greatly hamper the abilities of these creatures to produce their calcium carbonate skeletons. However, several experimental studies have cast great doubt on this theoretical contention, as may be readily seen by perusing the many materials we have archived in our Subject Index under the general heading of Calcification, while here we review yet another pertinent study.

What was done
Iglesias-Rodriguez et al. conducted several batch incubations of the phytoplanktonic coccolithophore species Emiliania hyxleyi while bubbling air of a number of different atmospheric CO2 concentrations through the culture medium and determining the amounts of particulate inorganic carbon (PIC) and particulate organic carbon (POC) produced by the coccolithophores within the different CO2 treatments. In addition, they determined the change in average coccolithophore mass over the past 220 years based on data obtained from a sediment core extracted from the subpolar North Atlantic Ocean, over which period of time the atmosphere's CO2 concentration rose by approximately 90 ppm.

What was learned
The thirteen researchers -- hailing from the United Kingdom, France and the United States -- observed an approximate doubling of both PIC and POC between the culture media in equilibrium with air of today's CO2 concentration and 750 ppm CO2. In addition, they write that the field evidence obtained from the deep-ocean sediment core they studied "is consistent with these laboratory conclusions, indicating that over the past 220 years there has been a 40% increase in average coccolith mass."

What it means
Once again we have a situation where real-world observations depict something that is just the opposite of a major theory-based prediction, the clear implication being that relevant environmental and energy policies must be based on the former and not the latter.

Reviewed 11 June 2008